square2.rb

gistfile1.rb

require "rubygems"
require "test/unit"

class Array
  def square
    self.each do |i|
      raise ArgumentError unless i.class == Float 
    end
     
     self.collect {|num| num * num}
     
  end
end


class TestLibraryFileName < Test::Unit::TestCase
  def test_case_name
    array = [1.0,2.0,3.0]
    assert_equal([1.0,4.0,9.0], array.square)    
  end
  
  def test_type
    array = ["a","b","c"]
    assert_raise(ArgumentError) { 
      array.square
    }
  end
end